Beam switch related information feedback in wireless communications

ABSTRACT

Methods, systems, and devices for wireless communications are described in which measurements of a number of beams that are transmitted from a first device, measured at a second device are provided in a beam switch metric report from the second device. The beam switch metric report may provide the first device with information that is otherwise unavailable to the first device and that may be used for setting beam management parameters.

CROSS REFERENCE

The present Application for Patent claims the benefit of U.S.Provisional Patent Application No. 62/784,339 by ZHOU, et al., entitled“BEAM SWITCH RELATED INFORMATION FEEDBACK IN WIRELESS COMMUNICATIONS,”filed Dec. 21, 2018, assigned to the assignee hereof, and expresslyincorporated herein.

BACKGROUND

The following relates generally to wireless communications, and morespecifically to beam switch related information feedback in wirelesscommunications.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform spread orthogonal frequency division multiplexing(DFT-S-OFDM). A wireless multiple-access communications system mayinclude a number of base stations or network access nodes, eachsimultaneously supporting communication for multiple communicationdevices, which may be otherwise known as user equipment (UE).

Some wireless multiple-access communications systems may include anumber of transmission/reception points (TRPs), such as base stations,network access nodes, or UEs (e.g., in a peer-to-peer ordevice-to-device deployment), each simultaneously supportingcommunication for multiple UEs or other network devices. In somewireless communications systems, a wireless devices (such as a basestation and UE) may communicate using directional beams (e.g.,directional transmit beams and directional receive beams) that form beampair links (BPLs) for exchanging data packets. In some cases, thewireless devices may modify one or more BPLs used to communicate, forexample, due to the mobility of one or both of the devices resulting ina change in a preferred directional transmit beam or directional receivebeam. However, conventional techniques for dynamically managing beamsmay be deficient.

SUMMARY

The described techniques relate to improved methods, systems, devices,and apparatuses that support beam switch related information feedback inwireless communications. Various described techniques provide formeasurements of a number of beams that are transmitted from a firstdevice (e.g., a base station) at a second device (e.g., a user equipment(UE)), and transmission of a beam switch metric report from the seconddevice. The beam switch metric report may provide the first device withinformation that is otherwise unavailable to the first device and thatmay be used for setting beam management parameters, such as resourcesfor reference signal transmissions, beam directions and periodicity ofchanges of preferred transmission beams, for example. In some cases, thesecond device may provide the beam switch metric report to a thirddevice (e.g., a master base station) which may identify beam refinementparameters and initial access resources (e.g., random access resources)for initiating a connection between the second device and the thirddevice (e.g., a secondary base station). In some cases, the seconddevice may perform measurements using a number of different receivebeams at the second device, and the beam switch metrics may provideinformation associated with a beam switch periodicity for switching thesecond device between two or more of the of receive beams.

A method of wireless communication at a device including is described.The method may include identifying a set of beams associated with afirst device, each of the set of beams of the first device having adifferent direction relative to the first device, determining, based onthe set of beams of the first device, one or more beam switch metricsassociated with a beam switch periodicity for switching a second devicebetween two or more of the set of beams of the first device, andtransmitting a report to the first device or a third device thatindicates the one or more beam switch metrics.

An apparatus for wireless communication at a device including isdescribed. The apparatus may include a processor, memory in electroniccommunication with the processor, and instructions stored in the memory.The instructions may be executable by the processor to cause theapparatus to identify a set of beams associated with a first device,each of the set of beams of the first device having a differentdirection relative to the first device, determine, based on the set ofbeams of the first device, one or more beam switch metrics associatedwith a beam switch periodicity for switching a second device between twoor more of the set of beams of the first device, and transmit a reportto the first device or a third device that indicates the one or morebeam switch metrics.

Another apparatus for wireless communication at a device including isdescribed. The apparatus may include means for identifying a set ofbeams associated with a first device, each of the set of beams of thefirst device having a different direction relative to the first device,determining, based on the set of beams of the first device, one or morebeam switch metrics associated with a beam switch periodicity forswitching a second device between two or more of the set of beams of thefirst device, and transmitting a report to the first device or a thirddevice that indicates the one or more beam switch metrics.

A non-transitory computer-readable medium storing code for wirelesscommunication at a device including is described. The code may includeinstructions executable by a processor to identify a set of beamsassociated with a first device, each of the set of beams of the firstdevice having a different direction relative to the first device,determine, based on the set of beams of the first device, one or morebeam switch metrics associated with a beam switch periodicity forswitching a second device between two or more of the set of beams of thefirst device, and transmit a report to the first device or a thirddevice that indicates the one or more beam switch metrics.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first device and thethird device may each be base stations, and the second device may be aUE. In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more beam switchmetrics provide information for setting beam management transmissions inaccordance with the beam switch periodicity for switching the seconddevice between the two or more of the set of beams of the first device.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the report may be transmittedto the third device, and the one or more beam switch metrics provideinformation for selecting a first transmission beam for transmitting aninitial access request to the first device. Some examples of the method,apparatuses, and non-transitory computer-readable medium describedherein may further include operations, features, means, or instructionsfor identifying a first time at which a first synchronization signalblock (SSB) transmission of the first device that has more favorablechannel conditions than one or more other SSB transmissions of the firstdevice, identifying a second time at which a second SSB transmission ofthe first device has more favorable channel conditions than the firstSSB transmission and one or more other of the SSB transmissions of thefirst device, and providing at least the first time and the second timeto the third device in a best SSB time trace (BST) beam switch metric.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving a controlinformation transmission from the third device that indicates the seconddevice is to transmit the initial access request to the first device,and that indicates one or more SSB transmissions of the first devicethat are to be monitored for reference signal transmissions to determinea preferred transmission beam for subsequent communications with thefirst device.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining, based onone or more of the beam switch metrics, the beam switch periodicity,where the beam switch periodicity indicates a rate at which transmissionbeams having more favorable transmission beam channel conditions thanother of the set of transmission beams changes at the second device, andtransmitting the determined beam switch periodicity to the first deviceor the second device.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the beam metrics may includeone or more of a speed of the second device, a Doppler shift of one ormore transmission beams observed at the second device, a distancebetween the second device and the first device, a dwelling time thatindicates an expected time duration during which a transmission beamwill may have more favorable channel conditions than any other of theset of transmission beams of the first device, a dwelling time thatindicates an expected time duration during which a receive beam of thesecond device will provide more favorable receive conditions than any ofa set of other receive beams of the second device, a time trace ofconsecutive transmission beams having a highest quality at the seconddevice for a prior time period, a second device movement profile thatincludes information related to the second device movement speed anddirection, spatial location changes, a calculated beam switchperiodicity, or any combinations thereof. In some examples of themethod, apparatuses, and non-transitory computer-readable mediumdescribed herein, the quality includes one or more of a received signalstrength or signal to interference and noise ratio (SINR).

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the beam switch metrics mayinclude statistics that include one or more of an average value of theassociated beam switch metric, a median value of the associated beamswitch metric, a percentile of the associated beam switch metric, amaximum value of the associated beam switch metric during apredetermined time period, a minimum value of the associated beam switchmetric during the predetermined time period, a histogram of observedbeam switch metrics for the predetermined time period, or anycombinations thereof.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining to transmitthe report based on a change in one or more of the beam switch metricsexceeding a threshold value. In some examples of the method,apparatuses, and non-transitory computer-readable medium describedherein, the report may be transmitted autonomously by the second device.Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving configurationinformation from the first device that indicates a periodicity fortransmitting the report, and transmitting the report according to theperiodicity for transmitting the report. In some examples of the method,apparatuses, and non-transitory computer-readable medium describedherein, the report may be transmitted in a medium access control (MAC)control element (CE). In some examples of the method, apparatuses, andnon-transitory computer-readable medium described herein, the reportfurther includes a cell identification associated with the one or morebeam switch metrics.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a set ofcells for which beam switch metrics are measurable, determining that atleast one cell of the set of cells is a mobile cell and that one or moreof the set of cells are stationary cells, and measuring the beam switchmetrics of the one or more stationary cells.

A method of wireless communication at a second device including isdescribed. The method may include identifying a set of receive beamsassociated with the second device, each of the set of receive beams ofthe second device having a different direction relative to the seconddevice, determining, based on the set of receive beams of the seconddevice, one or more beam switch metrics associated with a beam switchperiodicity for switching the second device between two or more of theset of receive beams, and transmitting a report to a first device or athird device that indicates the one or more beam switch metrics.

An apparatus for wireless communication at a second device including isdescribed. The apparatus may include a processor, memory in electroniccommunication with the processor, and instructions stored in the memory.The instructions may be executable by the processor to cause theapparatus to identify a set of receive beams associated with the seconddevice, each of the set of receive beams of the second device having adifferent direction relative to the second device, determine, based onthe set of receive beams of the second device, one or more beam switchmetrics associated with a beam switch periodicity for switching thesecond device between two or more of the set of receive beams, andtransmit a report to a first device or a third device that indicates theone or more beam switch metrics.

Another apparatus for wireless communication at a second deviceincluding is described. The apparatus may include means for identifyinga set of receive beams associated with the second device, each of theset of receive beams of the second device having a different directionrelative to the second device, determining, based on the set of receivebeams of the second device, one or more beam switch metrics associatedwith a beam switch periodicity for switching the second device betweentwo or more of the set of receive beams, and transmitting a report to afirst device or a third device that indicates the one or more beamswitch metrics.

A non-transitory computer-readable medium storing code for wirelesscommunication at a second device including is described. The code mayinclude instructions executable by a processor to identify a set ofreceive beams associated with the second device, each of the set ofreceive beams of the second device having a different direction relativeto the second device, determine, based on the set of receive beams ofthe second device, one or more beam switch metrics associated with abeam switch periodicity for switching the second device between two ormore of the set of receive beams, and transmit a report to a firstdevice or a third device that indicates the one or more beam switchmetrics.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first device and thethird device are each base stations, and the second device is a UE. Insome examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more beam switchmetrics provide information for setting beam management transmissions inaccordance with the beam switch periodicity for switching the seconddevice between the two or more of the set of receive beams of the seconddevice.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more beam switchmetrics include one or more of a speed of the second device, a Dopplershift of one or more transmission beams observed at the second device, adistance between the second device and the first device, a dwelling timethat indicates an expected time duration during which a transmissionbeam of the first device will may have more favorable channel conditionsthan any other of a set of transmission beams of the first device, adwelling time that indicates an expected time duration during which areceive beam of the second device will provide more favorable receiveconditions than any other of the set of receive beams of the seconddevice, a second device movement profile that includes informationrelated to the second device movement speed and direction, spatiallocation changes, a calculated beam switch periodicity, or anycombinations thereof.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more beam switchmetrics include statistics for one or more of an average value of theassociated beam switch metric, a median value of the associated beamswitch metric, a percentile of the associated beam switch metric, amaximum value of the associated beam switch metric during apredetermined time period, a minimum value of the associated beam switchmetric during the predetermined time period, a histogram of observedbeam switch metrics for the predetermined time period, or anycombinations thereof.

A method of wireless communication at a first device is described. Themethod may include establishing a connection with a second device,receiving, from the second device, a report that indicates one or morebeam switch metrics associated with a set of transmission beams receivedat the second device, determining, based on the report, one or more beammanagement parameters for one or more transmissions to the second devicevia one or more of the set of transmission beams, and transmitting theone or more beam management parameters to the second device.

An apparatus for wireless communication at a first device is described.The apparatus may include a processor, memory in electroniccommunication with the processor, and instructions stored in the memory.The instructions may be executable by the processor to cause theapparatus to establish a connection with a second device, receive, fromthe second device, a report that indicates one or more beam switchmetrics associated with a set of transmission beams received at thesecond device, determine, based on the report, one or more beammanagement parameters for one or more transmissions to the second devicevia one or more of the set of transmission beams, and transmit the oneor more beam management parameters to the second device.

Another apparatus for wireless communication at a first device isdescribed. The apparatus may include means for establishing a connectionwith a second device, receiving, from the second device, a report thatindicates one or more beam switch metrics associated with a set oftransmission beams received at the second device, determining, based onthe report, one or more beam management parameters for one or moretransmissions to the second device via one or more of the set oftransmission beams, and transmitting the one or more beam managementparameters to the second device.

A non-transitory computer-readable medium storing code for wirelesscommunication at a first device is described. The code may includeinstructions executable by a processor to establish a connection with asecond device, receive, from the second device, a report that indicatesone or more beam switch metrics associated with a set of transmissionbeams received at the second device, determine, based on the report, oneor more beam management parameters for one or more transmissions to thesecond device via one or more of the set of transmission beams, andtransmit the one or more beam management parameters to the seconddevice.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first device is a basestation, and the second device is a UE.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more beammanagement parameters include a beam switch periodicity for switchingthe second device between two or more of the set of transmission beams.In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first device may be aprimary base station in a non-stand-alone (NSA) deployment, and the setof transmission beams may be transmitted by a secondary base station inthe NSA deployment, and where the methods, apparatuses, andnon-transitory computer-readable medium described herein further mayinclude operations, features, means, or instructions for identifying, bythe first device based on the one or more beam switch metrics, a firsttransmission beam of the set of transmission beams for the second deviceto transmit an initial access request to the secondary base station.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, at least a subset of the setof transmission beams include a synchronization signal block (SSB)transmission from the secondary base station, and where the reportincludes a best SSB time trace (BST) beam switch metric that indicatestwo or more time periods and, for each of the two or more time periods,a preferred SSB of the second device.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for providing the secondarybase station with the BST beam switch metric received from the seconddevice, and transmitting to the second device, based on the BST beamswitch metric, control information for the second device monitor one ormore SSB transmissions and to transmit the initial access request.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining, based onone or more of the beam switch metrics, a beam switch periodicity of thesecond device that indicates a rate at which transmission beams havingmore favorable transmission beam channel conditions than other of theset of transmission beams changes at the second device, and where theone or more beam management parameters may be based on the beam switchperiodicity.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the one or more of the beamswitch metrics include one or more of a speed of the second device, aDoppler shift of one or more transmission beams observed at the seconddevice, a distance between the second device and the first device, adwelling time that indicates an expected time duration during which atransmission beam will may have more favorable channel conditions at thesecond device than any other of the set of transmission beams, adwelling time that indicates an expected time duration during which areceive beam of the second device will provide more favorable receiveconditions than any of a set of other receive beams of the seconddevice, a time trace of consecutive transmission beams having a highestreceived power at the second device for a prior time period, a seconddevice movement profile that includes information related to the seconddevice movement speed and direction, spatial location changes, acalculated beam switch periodicity, or any combinations thereof.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, one or more of the beamswitch metrics may include statistics that include one or more of anaverage value of the associated beam switch metric, a median value ofthe associated beam switch metric, a percentile of the associated beamswitch metric, a maximum value of the associated beam switch metricduring a predetermined time period, a minimum value of the associatedbeam switch metric during the predetermined time period, a histogram ofobserved beam switch metrics for the predetermined time period, or anycombinations thereof.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for configuring the seconddevice to transmit the report based on a change in one or more of thebeam switch metrics exceeding a threshold value. In some examples of themethod, apparatuses, and non-transitory computer-readable mediumdescribed herein, the report may be transmitted autonomously by thesecond device. Some examples of the method, apparatuses, andnon-transitory computer-readable medium described herein may furtherinclude operations, features, means, or instructions for configuring thesecond device to transmit the report according to a periodictransmission schedule, and monitoring for the report from the seconddevice according to the periodic transmission schedule. In some examplesof the method, apparatuses, and non-transitory computer-readable mediumdescribed herein, the report may be received in a MAC-CE from the seconddevice. In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the report further includes acell identification associated with the one or more beam switch metrics.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationsthat supports beam switch related information feedback in wirelesscommunications in accordance with aspects of the present disclosure.

FIG. 2 illustrates an example of a portion of a wireless communicationssystem that supports beam switch related information feedback inwireless communications in accordance with aspects of the presentdisclosure.

FIG. 3 illustrates an example of a dual connectivity deployment thatsupports beam switch related information feedback in wirelesscommunications in accordance with aspects of the present disclosure.

FIG. 4 illustrates an example of a best SSB time trace (BST) thatsupports beam switch related information feedback in wirelesscommunications in accordance with aspects of the present disclosure.

FIG. 5 illustrates an example of a process flow for secondary nodeaccess based on a BST in accordance with aspects of the presentdisclosure.

FIG. 6 illustrates an example of a process flow that supports beamswitch related information feedback in wireless communications inaccordance with aspects of the present disclosure.

FIGS. 7 and 8 show block diagrams of devices that support beam switchrelated information feedback in wireless communications in accordancewith aspects of the present disclosure.

FIG. 9 shows a block diagram of a communications manager that supportsbeam switch related information feedback in wireless communications inaccordance with aspects of the present disclosure.

FIG. 10 shows a diagram of a system including a device that supportsbeam switch related information feedback in wireless communications inaccordance with aspects of the present disclosure.

FIGS. 11 and 12 show block diagrams of devices that support beam switchrelated information feedback in wireless communications in accordancewith aspects of the present disclosure.

FIG. 13 shows a block diagram of a communications manager that supportsbeam switch related information feedback in wireless communications inaccordance with aspects of the present disclosure.

FIG. 14 shows a diagram of a system including a device that supportsbeam switch related information feedback in wireless communications inaccordance with aspects of the present disclosure.

FIGS. 15 through 19 show flowcharts illustrating methods that supportbeam switch related information feedback in wireless communications inaccordance with aspects of the present disclosure.

DETAILED DESCRIPTION

Some wireless communication systems may operate in millimeter wave (mmW)frequency ranges, e.g., 25 gigahertz (GHz), 40 GHz, 60 GHz, etc.Wireless communication at these frequencies may be associated withincreased signal attenuation (e.g., path loss), which may be influencedby various factors, such as temperature, barometric pressure,diffraction, etc. As a result, transmissions may be beamformed toovercome the path loss experienced at these frequencies. Wirelessdevices within such systems may accordingly communicate via directionalbeams (e.g., beamformed for transmission and reception using an antennaarray at the wireless device). For example, two or more wireless devicesmay communicate via beam pair links (BPLs), where each BPL includes atransmit beam of one wireless device (e.g., a user equipment (UE)) and areceive beam of another wireless device (e.g., a base station, anotherUE, a transmission/reception point (TRP), etc.).

Systems that employ transmission beams may use measurements related tomultiple beams to identify a best, or most preferred beam to use in aBPL. For example, a first wireless device (e.g., a base station) mayperform a beam sweep (e.g., a P1 beam training procedure) in whichconsecutive beams having a relatively wide beam width are transmittedand may be measured at a second wireless device (e.g., a UE) to identifya best beam (e.g., a beam with a highest reference signal received power(RSRP)) and provide an indication to the first wireless device of thepreferred beam. In some cases, further beam refinements may be performedin which the first wireless device may transmit one or more referencesignals (e.g., a channel state information (CSI) reference signal(CSI-RS) in a P2/P3 beam training procedure) in narrower beams toidentify more focused beams for use in BPLs.

Various aspects of the present disclosure provide that a second wirelessdevice (e.g., a UE, a TRP, etc.) may measure one or more beams of afirst wireless device (e.g., another UE, a base station, a TRP, etc.),identify one or more other parameters associated with the secondwireless device (e.g., speed, a movement profile, etc.), and determineone or more beam metrics. Such beam metrics may be provided to the firstwireless device or another wireless device, and may be used to determinebeam management parameters for beams in which to include referencesignal transmissions, periodicity of such reference signaltransmissions, and the like.

Such techniques may allow for enhanced beam management operations basedon beam metrics that are provided by the second wireless device, andthat may not be directly observable by the first wireless device orother wireless device that may perform beam management operations. Forexample, the first wireless device may be a base station thatestablishes an initial connection with the second wireless device whichmay be a UE. In such cases, the base station may need to configure beammanagement periodicity for newly connected UE after initial access, orhandover from another base station. However, base station may not haveany information related to, for example, how fast the UE may need toswitch beams (e.g., whether the UE is stationary, is travelling at arelatively high speed, is rotating with respect to the base station,etc.). In such cases, the report of beam metrics provided to the basestation may allow the base station to provide beam managementperiodicity that supports a beam switch periodicity of the UE.

In other cases, the base station may need to increase beam managementperiodicity for an existing UE whose speed suddenly increases. However,the base station is not able to directly detect the UE speed increasequickly if a current beam management periodicity is slow (e.g., when theUE changes from a stationary state to a moving state). In such cases,beam metric reporting provided by the UE in accordance with techniquesprovided herein may allow the base station to more quickly adapt thebeam management periodicity so beam switching can be performed.

Further, in some cases wireless devices may be deployed in aninternet-of-things (IoT) deployment such as an industrial IoT in whichthe devices may be associated with industrial equipment. In such cases,a first wireless device (e.g., a controller, base station, etc.) mayreceive beam metric reports from a second wireless device (e.g., a UEhaving an associated sensor, a robot arm, etc.). For example, acontroller may wirelessly communicate with motion control sensors ondifferent moving machines using beamformed communications. However, thecontroller may not be aware of the movement/rotation speed per sensor.In some cases, each sensor may can feed back its movement profile to thecontroller in accordance with techniques as discussed herein to enhanceperiodicity for beam management (e.g., enhance periodicity for a numberof beam management phases, such as P1/P2/P3 beam training and refinementprocedures).

In other cases, a first wireless device may provide a master node oranchor connection to a second wireless device, and a third wirelessdevice may use beamformed communications for a secondary connection withthe second wireless device. Such a deployment may be referred to as anon-stand-alone (NSA) mode, and the third wireless device may perform abeam sweep in which a number of synchronization signal blocks (SSBs) aretransmitted in successive beams. In some cases, the second device, whenperforming initial access with the third wireless device, may provide areport to the first wireless device that initiates access with the thirdwireless device. The first wireless device may use the report toconfigure random access channel (RACH) resources for an initial accesstransmission (e.g., a RACH message 1 (MSG1) transmission). However, ifthe second wireless device is moving relatively fast, or rotatingrelatively fast, a best beam at the second wireless device may havechanged during a time between the report and configuration of theinitial access resources. Using techniques as discussed herein, thesecond wireless device may provide a beam metric report that can feedback a time trace of the best beams observed at the UE to the firstwireless device, and which may be used to provide initial accessresources with a higher likelihood of successful communications.

Aspects of the disclosure are initially described in the context of awireless communications system. Further examples are then provided whichillustrate beam metric measurements are reporting, and the modificationof communications between devices using different BPLs and robustcommunications schemes. Aspects of the disclosure are furtherillustrated by and described with reference to apparatus diagrams,system diagrams, and flowcharts that relate to beam switch relatedinformation feedback in wireless communications.

FIG. 1 illustrates an example of a wireless communications system 100that supports beam switch related information feedback in wirelesscommunications in accordance with aspects of the present disclosure. Thewireless communications system 100 includes base stations 105, UEs 115,and a core network 130. In some examples, the wireless communicationssystem 100 may be a Long Term Evolution (LTE) network, an LTE-Advanced(LTE-A) network, an LTE-A Pro network, or a New Radio (NR) network. Insome cases, wireless communications system 100 may support enhancedbroadband communications, ultra-reliable (e.g., mission critical)communications, low latency communications, or communications withlow-cost and low-complexity devices. Wireless communications system 100may support the use of beam metric reports from UEs 115 (or otherwireless devices) that use BPLs that may allow for beam managementperiodicity to be adjusted in response to dynamically changingconditions.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Base stations 105 described herein mayinclude or may be referred to by those skilled in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation NodeB orgiga-NodeB (either of which may be referred to as a gNB), a Home NodeB,a Home eNodeB, or some other suitable terminology. Wirelesscommunications system 100 may include base stations 105 of differenttypes (e.g., macro or small cell base stations). The UEs 115 describedherein may be able to communicate with various types of base stations105 and network equipment including macro eNBs, small cell eNBs, gNBs,relay base stations, and the like.

Each base station 105 may be associated with a particular geographiccoverage area 110 in which communications with various UEs 115 issupported. Each base station 105 may provide communication coverage fora respective geographic coverage area 110 via communication links 125,and communication links 125 between a base station 105 and a UE 115 mayutilize one or more carriers. Communication links 125 shown in wirelesscommunications system 100 may include uplink transmissions from a UE 115to a base station 105, or downlink transmissions from a base station 105to a UE 115. Downlink transmissions may also be called forward linktransmissions while uplink transmissions may also be called reverse linktransmissions.

The geographic coverage area 110 for a base station 105 may be dividedinto sectors making up a portion of the geographic coverage area 110,and each sector may be associated with a cell. For example, each basestation 105 may provide communication coverage for a macro cell, a smallcell, a hot spot, or other types of cells, or various combinationsthereof. In some examples, a base station 105 may be movable andtherefore provide communication coverage for a moving geographiccoverage area 110. In some examples, different geographic coverage areas110 associated with different technologies may overlap, and overlappinggeographic coverage areas 110 associated with different technologies maybe supported by the same base station 105 or by different base stations105. The wireless communications system 100 may include, for example, aheterogeneous LTE/LTE-A/LTE-A Pro or NR network in which different typesof base stations 105 provide coverage for various geographic coverageareas 110.

The term “cell” refers to a logical communication entity used forcommunication with a base station 105 (e.g., over a carrier), and may beassociated with an identifier for distinguishing neighboring cells(e.g., a physical cell identifier (PCID), a virtual cell identifier(VCID)) operating via the same or a different carrier. In some examples,a carrier may support multiple cells, and different cells may beconfigured according to different protocol types (e.g., machine-typecommunication (MTC), narrowband Internet-of-Things (NB-IoT), enhancedmobile broadband (eMBB), or others) that may provide access fordifferent types of devices. In some cases, the term “cell” may refer toa portion of a geographic coverage area 110 (e.g., a sector) over whichthe logical entity operates.

UEs 115 may be dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile device, a wireless device, a remote device, ahandheld device, or a subscriber device, or some other suitableterminology, where the “device” may also be referred to as a unit, astation, a terminal, or a client. A UE 115 may also be a personalelectronic device such as a cellular phone, a personal digital assistant(PDA), a tablet computer, a laptop computer, or a personal computer. Insome examples, a UE 115 may also refer to a wireless local loop (WLL)station, an Internet of Things (IoT) device, an Internet of Everything(IoE) device, or an MTC device, or the like, which may be implemented invarious articles such as appliances, vehicles, meters, or the like.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay that information to acentral server or application program that can make use of theinformation or present the information to humans interacting with theprogram or application. Some UEs 115 may be designed to collectinformation or enable automated behavior of machines. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples half-duplexcommunications may be performed at a reduced peak rate. Other powerconservation techniques for UEs 115 include entering a power saving“deep sleep” mode when not engaging in active communications, oroperating over a limited bandwidth (e.g., according to narrowbandcommunications). In some cases, UEs 115 may be designed to supportcritical functions (e.g., mission critical functions), and a wirelesscommunications system 100 may be configured to provide ultra-reliablecommunications for these functions.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 (e.g., using a peer-to-peer (P2P) or device-to-device(D2D) protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the geographic coverage area 110 of a basestation 105. Other UEs 115 in such a group may be outside the geographiccoverage area 110 of a base station 105, or be otherwise unable toreceive transmissions from a base station 105. In some cases, groups ofUEs 115 communicating via D2D communications may utilize a one-to-many(1:M) system in which each UE 115 transmits to every other UE 115 in thegroup. In some cases, a base station 105 facilitates the scheduling ofresources for D2D communications. In other cases, D2D communications arecarried out between UEs 115 without the involvement of a base station105.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., via an S1, N2, N3, orother interface). Base stations 105 may communicate with one anotherover backhaul links 134 (e.g., via an X2, Xn, or other interface) eitherdirectly (e.g., directly between base stations 105) or indirectly (e.g.,via core network 130).

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC), which may include at least one mobilitymanagement entity (MME), at least one serving gateway (S-GW), and atleast one Packet Data Network (PDN) gateway (P-GW). The MME may managenon-access stratum (e.g., control plane) functions such as mobility,authentication, and bearer management for UEs 115 served by basestations 105 associated with the EPC. User IP packets may be transferredthrough the S-GW, which itself may be connected to the P-GW. The P-GWmay provide IP address allocation as well as other functions. The P-GWmay be connected to the network operators IP services. The operators IPservices may include access to the Internet, Intranet(s), an IPMultimedia Subsystem (IMS), or a Packet-Switched (PS) Streaming Service.

At least some of the network devices, such as a base station 105, mayinclude subcomponents such as an access network entity, which may be anexample of an access node controller (ANC). Each access network entitymay communicate with UEs 115 through a number of other access networktransmission entities, which may be referred to as a radio head, a smartradio head, or a transmission/reception point (TRP). In someconfigurations, various functions of each access network entity or basestation 105 may be distributed across various network devices (e.g.,radio heads and access network controllers) or consolidated into asingle network device (e.g., a base station 105).

Wireless communications system 100 may operate using one or morefrequency bands, typically in the range of 300 megahertz (MHz) to 300gigahertz (GHz). Generally, the region from 300 MHz to 3 GHz is known asthe ultra-high frequency (UHF) region or decimeter band, since thewavelengths range from approximately one decimeter to one meter inlength. UHF waves may be blocked or redirected by buildings andenvironmental features. However, the waves may penetrate structuressufficiently for a macro cell to provide service to UEs 115 locatedindoors. Transmission of UHF waves may be associated with smallerantennas and shorter range (e.g., less than 100 km) compared totransmission using the smaller frequencies and longer waves of the highfrequency (HF) or very high frequency (VHF) portion of the spectrumbelow 300 MHz.

Wireless communications system 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band. The SHF region includes bands such as the5 GHz industrial, scientific, and medical (ISM) bands, which may be usedopportunistically by devices that may be capable of toleratinginterference from other users.

Wireless communications system 100 may also operate in an extremely highfrequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz),also known as the millimeter band. In some examples, wirelesscommunications system 100 may support millimeter wave (mmW)communications between UEs 115 and base stations 105, and EHF antennasof the respective devices may be even smaller and more closely spacedthan UHF antennas. In some cases, this may facilitate use of antennaarrays within a UE 115. However, the propagation of EHF transmissionsmay be subject to even greater atmospheric attenuation and shorter rangethan SHF or UHF transmissions. Techniques disclosed herein may beemployed across transmissions that use one or more different frequencyregions, and designated use of bands across these frequency regions maydiffer by country or regulating body.

In some cases, wireless communications system 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communications system 100 may employ License Assisted Access(LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technologyin an unlicensed band such as the 5 GHz ISM band. When operating inunlicensed radio frequency spectrum bands, wireless devices such as basestations 105 and UEs 115 may employ listen-before-talk (LBT) proceduresto ensure a frequency channel is clear before transmitting data. In somecases, operations in unlicensed bands may be based on a carrieraggregation configuration in conjunction with component carriersoperating in a licensed band (e.g., LAA). Operations in unlicensedspectrum may include downlink transmissions, uplink transmissions,peer-to-peer transmissions, or a combination of these. Duplexing inunlicensed spectrum may be based on frequency division duplexing (FDD),time division duplexing (TDD), or a combination of both.

In some examples, base station 105 or UE 115 may be equipped withmultiple antennas, which may be used to employ techniques such astransmit diversity, receive diversity, multiple-input multiple-output(MIMO) communications, or beamforming. For example, wirelesscommunications system 100 may use a transmission scheme between atransmitting device (e.g., a base station 105) and a receiving device(e.g., a UE 115), where the transmitting device is equipped withmultiple antennas and the receiving device is equipped with one or moreantennas. MIMO communications may employ multipath signal propagation toincrease the spectral efficiency by transmitting or receiving multiplesignals via different spatial layers, which may be referred to asspatial multiplexing. The multiple signals may, for example, betransmitted by the transmitting device via different antennas ordifferent combinations of antennas. Likewise, the multiple signals maybe received by the receiving device via different antennas or differentcombinations of antennas. Each of the multiple signals may be referredto as a separate spatial stream, and may carry bits associated with thesame data stream (e.g., the same codeword) or different data streams.Different spatial layers may be associated with different antenna portsused for channel measurement and reporting. MIMO techniques includesingle-user MIMO (SU-MIMO) where multiple spatial layers are transmittedto the same receiving device, and multiple-user MIMO (MU-MIMO) wheremultiple spatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam or receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that signals propagating atparticular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying certain amplitude and phase offsets to signals carried via eachof the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

In one example, a base station 105 may use multiple antennas or antennaarrays to conduct beamforming operations for directional communicationswith a UE 115. For instance, some signals (e.g., synchronizationsignals, reference signals, beam selection signals, or other controlsignals) may be transmitted by a base station 105 multiple times indifferent directions, which may include a signal being transmittedaccording to different beamforming weight sets associated with differentdirections of transmission. Transmissions in different beam directionsmay be used to identify (e.g., by the base station 105 or a receivingdevice, such as a UE 115) a beam direction for subsequent transmissionand/or reception by the base station 105.

Some signals, such as data signals associated with a particularreceiving device, may be transmitted by a base station 105 in a singlebeam direction (e.g., a direction associated with the receiving device,such as a UE 115). In some examples, the beam direction associated withtransmissions along a single beam direction may be determined based atleast in in part on a signal that was transmitted in different beamdirections. For example, a UE 115 may receive one or more of the signalstransmitted by the base station 105 in different directions, and the UE115 may report to the base station 105 an indication of the signal itreceived with a highest signal quality, or an otherwise acceptablesignal quality. Although these techniques are described with referenceto signals transmitted in one or more directions by a base station 105,a UE 115 may employ similar techniques for transmitting signals multipletimes in different directions (e.g., for identifying a beam directionfor subsequent transmission or reception by the UE 115), or transmittinga signal in a single direction (e.g., for transmitting data to areceiving device).

A receiving device (e.g., a UE 115, which may be an example of a mmWreceiving device) may try multiple receive beams when receiving varioussignals from the base station 105, such as synchronization signals,reference signals, beam selection signals, or other control signals. Forexample, a receiving device may try multiple receive directions byreceiving via different antenna subarrays, by processing receivedsignals according to different antenna subarrays, by receiving accordingto different receive beamforming weight sets applied to signals receivedat a plurality of antenna elements of an antenna array, or by processingreceived signals according to different receive beamforming weight setsapplied to signals received at a plurality of antenna elements of anantenna array, any of which may be referred to as “listening” accordingto different receive beams or receive directions. In some examples areceiving device may use a single receive beam to receive along a singlebeam direction (e.g., when receiving a data signal). The single receivebeam may be aligned in a beam direction determined based at least inpart on listening according to different receive beam directions (e.g.,a beam direction determined to have a highest signal strength, highestsignal-to-noise ratio, or otherwise acceptable signal quality based atleast in part on listening according to multiple beam directions).

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays, which may support MIMOoperations, or transmit or receive beamforming. For example, one or morebase station antennas or antenna arrays may be co-located at an antennaassembly, such as an antenna tower. In some cases, antennas or antennaarrays associated with a base station 105 may be located in diversegeographic locations. A base station 105 may have an antenna array witha number of rows and columns of antenna ports that the base station 105may use to support beamforming of communications with a UE 115.Likewise, a UE 115 may have one or more antenna arrays that may supportvarious MIMO or beamforming operations.

In some cases, wireless communications system 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A Radio Link Control (RLC) layer mayperform packet segmentation and reassembly to communicate over logicalchannels. A Medium Access Control (MAC) layer may perform priorityhandling and multiplexing of logical channels into transport channels.The MAC layer may also use hybrid automatic repeat request (HARM) toprovide retransmission at the MAC layer to improve link efficiency. Inthe control plane, the Radio Resource Control (RRC) protocol layer mayprovide establishment, configuration, and maintenance of an RRCconnection between a UE 115 and a base station 105 or core network 130supporting radio bearers for user plane data. At the Physical layer,transport channels may be mapped to physical channels.

Time intervals in LTE or NR may be expressed in multiples of a basictime unit, which may, for example, refer to a sampling period ofT_(s)=1/30,720,000 seconds. Time intervals of a communications resourcemay be organized according to radio frames each having a duration of 10milliseconds (ms), where the frame period may be expressed asT_(f)=307,200 T_(s). The radio frames may be identified by a systemframe number (SFN) ranging from 0 to 1023. Each frame may include 10subframes numbered from 0 to 9, and each subframe may have a duration of1 ms. A subframe may be further divided into 2 slots each having aduration of 0.5 ms, and each slot may contain 6 or 7 modulation symbolperiods (e.g., depending on the length of the cyclic prefix prepended toeach symbol period). Excluding the cyclic prefix, each symbol period maycontain 2048 sampling periods. In some cases, a subframe may be thesmallest scheduling unit of the wireless communications system 100, andmay be referred to as a transmission time interval (TTI). In othercases, a smallest scheduling unit of the wireless communications system100 may be shorter than a subframe or may be dynamically selected (e.g.,in bursts of shortened TTIs (sTTIs) or in selected component carriersusing sTTIs).

In some wireless communications systems, a slot may further be dividedinto multiple mini-slots containing one or more symbols. In someinstances, a symbol of a mini-slot or a mini-slot may be the smallestunit of scheduling. Each symbol may vary in duration depending on thesubcarrier spacing or frequency band of operation, for example. Further,some wireless communications systems may implement slot aggregation inwhich multiple slots or mini-slots are aggregated together and used forcommunication between a UE 115 and a base station 105.

The term “carrier” refers to a set of radio frequency spectrum resourceshaving a defined physical layer structure for supporting communicationsover a communication link 125. For example, a carrier of a communicationlink 125 may include a portion of a radio frequency spectrum band thatis operated according to physical layer channels for a given radioaccess technology. Each physical layer channel may carry user data,control information, or other signaling. A carrier may be associatedwith a pre-defined frequency channel (e.g., an evolved universal mobiletelecommunication system terrestrial radio access (E-UTRA) absoluteradio frequency channel number (EARFCN)), and may be positionedaccording to a channel raster for discovery by UEs 115. Carriers may bedownlink or uplink (e.g., in an FDD mode), or be configured to carrydownlink and uplink communications (e.g., in a TDD mode). In someexamples, signal waveforms transmitted over a carrier may be made up ofmultiple sub-carriers (e.g., using multi-carrier modulation (MCM)techniques such as orthogonal frequency division multiplexing (OFDM) ordiscrete Fourier transform spread OFDM (DFT-S-OFDM)).

The organizational structure of the carriers may be different fordifferent radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR).For example, communications over a carrier may be organized according toTTIs or slots, each of which may include user data as well as controlinformation or signaling to support decoding the user data. A carriermay also include dedicated acquisition signaling (e.g., synchronizationsignals or system information, etc.) and control signaling thatcoordinates operation for the carrier. In some examples (e.g., in acarrier aggregation configuration), a carrier may also have acquisitionsignaling or control signaling that coordinates operations for othercarriers.

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). Insome examples, each served UE 115 may be configured for operating overportions or all of the carrier bandwidth. In other examples, some UEs115 may be configured for operation using a narrowband protocol typethat is associated with a predefined portion or range (e.g., set ofsubcarriers or RBs) within a carrier (e.g., “in-band” deployment of anarrowband protocol type).

In a system employing MCM techniques, a resource element may consist ofone symbol period (e.g., a duration of one modulation symbol) and onesubcarrier, where the symbol period and subcarrier spacing are inverselyrelated. The number of bits carried by each resource element may dependon the modulation scheme (e.g., the order of the modulation scheme).Thus, the more resource elements that a UE 115 receives and the higherthe order of the modulation scheme, the higher the data rate may be forthe UE 115. In MIMO systems, a wireless communications resource mayrefer to a combination of a radio frequency spectrum resource, a timeresource, and a spatial resource (e.g., spatial layers), and the use ofmultiple spatial layers may further increase the data rate forcommunications with a UE 115.

A base station 105 may transmit synchronization signal (SS) sequences tomultiple UEs 115, and a UE 115 may attempt to detect the SS sequences bycorrelating received SS signals with the SS sequences. In some examples,the SSs may be transmitted by the base station 105 using one or moreSSBs (e.g., time-frequency resources used for the transmission of SSs).For example, PSS, SSS, and/or broadcast information (e.g., a physicalbroadcast channel (PBCH)) may be transmitted within different SSBs onrespective directional beams or on different time/frequency resources.In some cases, one or more SSBs may be included within an SS burst.Additionally, SSBs may be quasi-co located (QCL'ed) with other signalstransmitted within wireless communications system 100.

A UE 115 may be configured with one or more transmission configurationindicator (TCI) state configurations. Different TCI states,distinguished by different values of the TCI, may correspond to quasico-location (QCL) relationships with different reference signaltransmissions. For example, each TCI state may be associated with one ofthe previously received reference signals. The TCI state may provide aspatial QCL reference that the UE 115 can use to set the receive beam.By configuring the TCI states at the UE 115, the base station 105 candynamically select beams for downlink transmission to the UE 115, andthe UE 115 can select the corresponding receive beam to receive thedownlink transmission. For a downlink transmission, the base station 105may transmit an indication of the TCI state to the UE 115, and the UE115 may select the corresponding receive beam based on the indicated TCIstate to receive the downlink transmission. The TCI states may beconfigured via higher layer signaling.

Wireless communications system 100 may support beam switch metricreporting techniques that provide for measurements of a number of beamsthat are transmitted from a first device (e.g., a controlling wirelessdevice, which may be an example of a base station 105, a TRP, a UE 115,a motion controller, etc.) at a second device (e.g., a secondarywireless device, which may be an example of a UE 115). The beam switchmetric reporting may provide the first device with information that isotherwise unavailable to the first device and that may be used forsetting beam management parameters, such as resources for referencesignal transmissions, beam directions and periodicity of changes ofpreferred transmission beams, for example. In some cases, the seconddevice may provide the beam switch metric report to a third device(e.g., a master base station 105) which may identify beam refinementparameters and initial access resources (e.g., random access resources)for initiating a connection between the second device and the thirddevice (e.g., a secondary base station). In some cases, the seconddevice may perform measurements using a number of different receivebeams at the second device, and the beam switch metrics may provideinformation associated with a beam switch periodicity for switching thesecond device between two or more of the of receive beams.

FIG. 2 illustrates an example of a wireless communications system 200that supports beam switch related information feedback in wirelesscommunications in accordance with aspects of the present disclosure. Insome examples, wireless communications system 200 may implement aspectsof wireless communications system 100. For example, wirelesscommunications system 200 may include a base station 105-a and a UE115-a, which may be examples of the corresponding devices described withreference to FIG. 1.

In wireless communications system 200, base station 105-a and UE 115-amay communicate using directional beams. For example, base station 105-amay use beamforming techniques to form a set of base station beams 205used for transmitting and receiving wireless signals. Likewise, UE115-a, at an initial time (T₁) may form a set of UE beams 210-a fortransmitting and receiving wireless signals. In some cases, UE 115-a andbase station 105-a may perform procedures to identify one or more beamsthat provide a highest signal or link quality (e.g., compared to otherbeams within a set of base station beams 205 and UE beams 210-a), whichmay include the measurement of one or more reference signals (e.g.,CSI-RS, SSBs, etc.) transmitted by base station 105-a. UE 115-a and basestation 105-a may each identify one or more pairs of corresponding beamsthat provide a link to communicate data between the devices. As such, UE115-a and base station 105-a may establish a communication link using afirst beam pair link 215.

As an example of establishing a communication link, the BPL 215 mayinclude a transmission beam formed by the transmitting entity anddirectional listening implemented by the receiving entity. For example,in downlink communications, base station 105-a may use a phased-arrayantenna to form a directional transmission beam and UE 115-a may usedirectional listening. In some cases, a base station beam 205 (e.g.,directional listening beam or transmission beam) formed by base station105-a may be larger than a UE beam 210 (e.g., a transmission beam ordirection listening) formed by UE 115-a (e.g., because base station105-a may have a larger array of antennas to perform beamforming). Inuplink communications, the roles of base station 105-a and UE 115-a maybe reversed. In some cases, wireless communications system 200 mayoperate in shared radio frequency band spectrum. As such, wirelesscommunications system 200 may use contention-based protocols to gainaccess communication resources. In other examples, wirelesscommunications system 200 may operate in licensed radio frequencyspectrum bands, where communications may be scheduled by base station105-a.

UE 115-a and base station 105-a may switch between different BPLs 215,for example, based on the movement and/or location of UE 115-a. Forexample, the UE 115-a may move, as indicated at 220, to a differentlocation at a later time (T₂) and UE beams 210-b and base station beams205 may result in a second beam pair link 225 providing a betterconnection for communications. As such, BPL switching performed by UE115-a and base station 105-a may be performed. However, as indicatedabove, in cases where the movement of the UE 115-a at time T₂ results ina beam switching periodicity that is different that a beam switchingperiodicity that is established at T₁, switching from the first BPL 215to the second BPL 225 may be performed late, which can degradeperformance and reliability of the system. Thus, in accordance withvarious techniques discussed herein, the UE 115-a may transmit a beamswitch metric report to the base station 105-a that may allow for beammanagement periodicities that are adjusted based on current conditions.Such techniques may provide enhanced beam management performance toallow for efficient and timely beam switching, while also using anappropriate amount of overhead based on current conditions (e.g., CSI-RSresources may be reduced for relatively slow beam switch periodicitiesand increased for relatively fast beam switch periodicities).

In some cases, the UE 115-a may transmit one or more reports thatinclude beam switch related metrics to the base station 105-a. The basestation 105-a may use the beam switch metrics to determine, for example,beam management periodicities (e.g., individual P1/P2/P3 BM periodicity)to save overhead and power consumption, while maintaining good BPLquality. Additionally or alternatively, the base station 105-a may usethe beam switch metrics to predict a best SSB beam for initial access ofthe UE 115-a with a second base station in a NSA mode of operation, aswill be discussed in more detail with respect to FIGS. 3 through 5.

In some cases, the beam switch metrics may include one or more of anumber of different metrics. For example, a first metric may be providedthat includes statistics of speed, Doppler shift, distance between theUE 115-a and base station (105-a), which may be used in some examples todetermine P1/P2 periodicity. In some cases, the first metric may alsoinclude statistics of angular speed of the UE, and a UE beam width,which may be used in some examples to determine P3 periodicity. In somecases a second metric may include statistics of dwelling time of bestbase station 105-a beams (e.g., SSB beams for P1/P2 periodicity),statistics of dwelling time of best UE 115-a beams (e.g., for P3periodicity), or combinations thereof. In some cases, a third metric mayinclude a time trace of best base station 105-a beams (e.g., SSB beamsfor P1 periodicity, and for best SSB prediction). In some cases, afourth metric may include a UE 115-a movement profile, which may includestatistics on movement/rotation speed and direction, spatial locationchange range, and the like. In some cases, statistics of the fourthmetric may be quantized or classified into different ranges or types andmay be signaled by a corresponding profile index/indicator (e.g., forP1/P2/P3 periodicity). In some cases, a fifth metric may include arecommended beam management periodicity that is provided by the UE 115-a(e.g., a recommended P1/P2/P3 periodicity).

In some cases, the UE 115-a may transmit a beam metric report thatincludes one or more of such metrics in accordance with a configurationprovided by the base station 105-a. In some cases, the UE 115-a maytransmit a beam metric report when the base station 105-a hasinsufficient or outdated information on UE 115-a movement. For example,a report may be transmitted before beam management is configured by thebase station 105-a (e.g., at initial access, handover, or before normaloperation of industrial IoT devices), or when beam switch periodicityshould be changed (e.g., if the best SSB changes faster or slower than aconfigured P1 report period). In some cases, the UE 115-a mayautonomously transmit the beam metric report (e.g., in a medium accesscontrol (MAC) control element (MAC-CE) that is configured for such areport). In some cases, the base station 105-a may configure the UE115-a for periodic or event-triggered reports (e.g., when a metricexceeds an associated threshold, such as a speed of the UE changing bymore than a threshold percentage during a time period). In some cases,the statistics reported in a beam metric report may include, for a timeperiod, one or more of an average value, a percentile value, a maximumvalue, a minimum value, a histogram computed in a time window (e.g., Xms before the report), or any combinations thereof. Additionally, insome cases, the beam metric report may include a cell ID for eachreported metric, which may enable the base station 105-a to loadcorresponding cell locations and SSB beam width to better determine beammanagement periodicity. In some cases, the UE 115-a may only measurestationary cells, and cells may be configured to broadcast a stationaryor mobile flag that the UE 115-a may use to distinguish stationary andmobile cells.

In one example, for a periodicity of a beam training procedure todetermine a best SSB of the base station 105-a at the UE 115-a (i.e., aP1 periodicity), the UE 115-a may provide a beam metric report thatindicates, for a 10° P1 beam, that the UE has a speed of 72 km/h and adistance of 5 meters from the base station 105-b. Thus, a P1 beamdwelling time is 40 ms, which may be used for beam managementperiodicity determination. In some cases, the UE 115-a or base station105-a may determine a corresponding P1 periodicity as 4 ms, to detect aP1 transmit beam change with detection latency of less than 10% of thedwelling time.

In another example, for a beam refinement periodicity (i.e., a P2periodicity), the UE 115-a may provide a beam metric report thatindicates, for a 3° P2 beam, that the UE has a speed of 72 km/h and adistance of 5 meters from the base station 105-b. Thus a P2 beamdwelling time is 10 ms which may be used for beam management periodicitydetermination. In some cases, the UE 115-a or base station 105-a maydetermine a corresponding P2 periodicity as 1 ms, to detect a P2transmit beam change with detection latency of less than 10% of thedwelling time.

In a further example, for a UE 115-a receive beam refinement periodicity(i.e., a P3 periodicity), the UE 115-a may provide a beam metric reportthat indicates that the UE 115-a has 20° receive beam (i.e., 9 beamscovering 180°) and rotates at a rate of 360° per second. In such cases,the best receive beam will change after UE rotates 20°, which iscorresponds to 56 ms. In some cases, the UE 115-a or base station 105-amay then determine a corresponding P3 periodicity that is at most 5 ms,to quickly detect P3 receive beam changes. The P1 periodicities maycorrespond to SSB transmission periodicities, and the P3/P3periodicities may correspond to CSI-RS periodicities.

It is noted that the operations described herein performed by a UE 115and base station 105 may be respectively performed by a UE 115, a basestation 105, or another wireless device, and the examples shown shouldnot be construed as limiting. For instance, the operations shown asperformed by base station 105-a may be performed by a UE 115, a TRP, oranother wireless device.

FIG. 3 illustrates an example of a dual connectivity NSA deployment 300that supports beam switch related information feedback in wirelesscommunications in accordance with aspects of the present disclosure. Insome examples, dual connectivity deployment 300 may implement aspects ofwireless communications system 100 or 200. In this example, a UE 115-bmay establish a connection 305 with a first base station 105-b (whichmay be an example of a first device), which may be a master nodeoperating in a first frequency range (e.g., FR1 or a sub-6 GHz frequencyrange). The UE 115-b may desire to establish a concurrent connectionwith a second base station 105-c (which may be an example of a thirddevice, where the UE 115-b is a second device), which may be a secondarynode in a NSA deployment that operates in a second frequency range(e.g., FR2 or a millimeter wave frequency range) that uses beamformedcommunications. The first base station 105-b and the second base station105-c may be connected via a backhaul link 134-a.

In some cases, the UE 115-b may measure one or more signals from a setof beams 310 of the second base station 105-c, such as SSBs transmittedin successive beams, and generate a best SSB time trace (BST). The BST,as will be discussed in more detail with respect to FIG. 4, may providetiming information associated with when different beams have a highestquality (e.g., a highest RSRP). In some cases, the UE 115-b may providethe BST to the first base station 105-b in a beam metric report. Thefirst base station 105-b may then, based on the BST provided by the UE115-b, predict a best SSB for a RACH procedure for the UE 115-a toperform an initial access procedure with the second base station 105-b(e.g., a best SSB for transmissions of RACH MSG1/MSG2/MSG3). In suchcases, the first base station 105-a (or other network node) may onlyneed to configure CSI-RS resources that are QCL'ed with the best SSB forthe RACH procedure (e.g., for P2/P3 beam management for MSG1/2/3). TheBST provided by the UE 115-b may also be used by the first base station105-b or the second base station 105-c to determine regular beammanagement periodicity after initial access (e.g., after MSG1/2/3). Forexample, P1 periodicity can be based on SSB beam dwelling time estimatedbased on the BST.

FIG. 4 illustrates an example of a best SSB time trace (BST) 400 thatsupports beam switch related information feedback in wirelesscommunications in accordance with aspects of the present disclosure. Insome examples, best SSB time trace (BST) 400 may implement aspects ofwireless communications system 100 or 300. In this example, the UE mayprovide a BST 425 that includes a time that a given SSB of a given cellon the second frequency range (e.g., FR2) becomes a best SSB (e.g.,based on RSRP).

In the example of FIG. 4, the UE may measure a RSRP from a first SSB 405that exceed other RSRPs of other SSBs, and identify a first time (T₁).SSBs may be transmitted according to SSB period 440 in this example, andthe first time may be provided as an indication of a SSB period index,in some examples. At a second time (T₂), the UE may determine that asecond SSB RSRP 410 is higher than other RSRPs, and may record T₂ in theBST 425. Likewise, at a third time (T₃) the UE may determine that athird SSB RSRP 415 is higher than other RSRPs, and may record T₃ in theBST 425. The BST 425 may be provided to a base station (e.g., a masternode in a NSA dual connectivity (DC) deployment), which may determine abest SSB to be used by the UE for a subsequent initial access procedure,as will be discussed in more detail in FIG. 5. In some cases, the UE mayonly record BST for stationary cells, since predicting a best SSB orcell may only be accurate for stationary cells (e.g., based on astationary/mobile flag). In some cases, the UE may only record andreport BST 425 when a speed of the UE exceeds a threshold value, sinceprediction may not be necessary for stationary or relatively slowspeeds. In some cases, the threshold value for such speed may beconfigured by the base station.

FIG. 5 illustrates an example of a process flow 500 for secondary nodeaccess based on a BST that supports beam switch related informationfeedback in wireless communications in accordance with aspects of thepresent disclosure. In some examples, process flow 500 may implementaspects of wireless communications system 100, 200, or 300. In thisexample, a first device 505 (e.g., a master node or master base station)may establish a connection with a second device 510 (e.g., a UE). Thesecond device 510 may desire to establish a secondary connection with athird device 515 (e.g., a secondary node or secondary base station) thatuses beamformed communications.

In this example, the third device 515 may transmit SSB bursts 520, whichmay include a number of SSBs, such as a first SSB 525, a second SSB 530,and a third SSB 535, using associated transmit beams. The second device510 may measure signals provided in the SSB bursts 520 (e.g., a RSRP)and record a BST, such as discussed with respect to FIG. 4. The seconddevice 510 may, at 540, transmit a L3 report that identifies the cellIDs and SSBs that are measured, and the BST to the first device 505.

At 545, the first device 505 may identify one or more predicted bestSSBs for an initial access procedure of the second device 510 with thethird device 515. In some cases, the predicted best SSBs may bedetermined based on a rate of change of best SSBs indicated the BST, anda time period between the BST and the initial access. The first device505 may provide information related to the second device 510 and thepredicted best SSBs to the third device.

At 550, the third device 515 may configure CSI-RS resources for thepredicted best SSBs, and initiate CSI-RS transmissions for beammanagement (e.g., P2/P3 procedures). In this example, the third device515 may configure CSI-RS for P2/P3 only for SSB2 and SSB3, which maysave overhead and latency relative to configurations that provide CSI-RSfor P2/P3 on additional SSBs.

At 555, the first device 505 may configure a PSCell addition and RACHconfiguration for the second device 510, and provide such information tothe second device 510 for initiating access with the third device 515.The third device 515 may transmit CSI-RSs using the identified bestSSBs. In this example, the first device 505 may identify SSB2 and SSB3as the best SSBs, and the third device 515 may transmit CSI-RStransmissions 560 that are QCL'ed with SSB2, and CSI-RS transmissions565 that are QCL'ed with SSB3. The second device 510, at 570, mayperform P2/P3 measurements on the CSI-RS transmissions and identify aparticular RACH resource 570 (e.g., a RACH resource that is QCL'ed withSSB3 based on the measurements at the second device 510).

At 575, the second device 510 may transmit a RACH MSG1 transmission tothe third device 515. The third device 515 may receive the MSG1transmission, and identify that a beam associated with SSB3 was used forthe transmission. At 580, the third device 515 may transmit a responsiveMSG2 transmission to the second device 510 using the identified beamassociated with SSB3. The second device 510 may then, at 585 transmit aRACH MSG3 transmission to the third device 515, and RRC connectionestablishment signaling may be used to complete the connection betweenthe second device 510 and the third device 515.

FIG. 6 illustrates an example of a process flow 600 that supports beamswitch related information feedback in wireless communications inaccordance with aspects of the present disclosure. In some examples,process flow 600 may implement aspects of wireless communications system100, 200, or 300. In this example, process flow 600 includes a firstwireless device 605, which may be an example of a base station 105, aTRP, or a UE 115, as described with reference to FIGS. 1 through 3.Additionally, process flow 600 includes a second wireless device 610,which may be an example of a UE 115 or another device that communicateswith, for example, the first wireless device 605.

At 615, the first wireless device 605 may transmit a number oftransmission beams. Such transmission beams may include SSBs, CSI-RStransmissions, or combinations thereof, which may be used for beammanagement by the first wireless device 605 and the second wirelessdevice 610 (e.g., P1/P2/P3 procedures).

At 620, the second wireless device 610 may perform measurements based onsignals received via the transmit beams. Such measurements may include,for example, RSRP measurements, signal to interference and noise ratio(SINR) measurements, Doppler measurements, and the like. In some cases,the second wireless device 610 may also measure one or more otherparameters, such as a speed of the device, a distance to the firstwireless device 605, an angular speed of the device, beam dwellingtimes, movement profiles, or any combinations thereof.

At 625, the second wireless device 610 may determine one or more beamswitch metrics. In some cases, such beam switch metrics may include oneor more of a speed of the second wireless device 610, a Doppler shift ofone or more transmission beams observed at the second wireless device610, a distance between the second wireless device 610 and the firstwireless device 605, a dwelling time that indicates an expected timeduration during which a transmission beam will have more favorablechannel conditions than any other of the set of transmission beams ofthe first device, a dwelling time that indicates an expected timeduration during which a receive beam of the second wireless device 610will provide more favorable receive conditions than any of a set ofother receive beams of the second wireless device 610, a time trace ofconsecutive transmission beams having a highest quality at the secondwireless device 610 for a prior time period, a second wireless device610 movement profile that includes information related to the secondwireless device 610 movement speed and direction, spatial locationchanges, a calculated beam switch periodicity, or any combinationsthereof. The second wireless device 610 may transmit, at 630, a beamswitch metrics report to the first wireless device 605.

At 635, the first wireless device 605 may determine one or more beammanagement parameters based on the beam switch metrics report. In somecases, the first wireless device 605 may adjust a periodicity and beamsfor transmissions of reference signals, such as synchronization signalsor CSI-RS transmissions. Such adjustments may provide sufficient signalsfor reliable beam switching, while reducing overhead by avoidingtransmissions that are not needed to maintain connectivity via thebeams. The first wireless device 605 may transmit, at 640, beam switchmanagement parameters to the second wireless device 610. The firstwireless device 605 and the second wireless device 610 may thencommunicate, at 645, in accordance with the provided beam switchmanagement parameters.

FIG. 7 shows a block diagram 700 of a device 705 that supports beamswitch related information feedback in wireless communications inaccordance with aspects of the present disclosure. The device 705 may bean example of aspects of a UE 115 as described herein. The device 705may include a receiver 710, a communications manager 715, and atransmitter 720. The device 705 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 710 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to beam switchrelated information feedback in wireless communications, etc.).Information may be passed on to other components of the device 705. Thereceiver 710 may be an example of aspects of the transceiver 1020described with reference to FIG. 10. The receiver 710 may utilize asingle antenna or a set of antennas.

The communications manager 715 may identify a set of beams associatedwith a first device, each of the set of beams of the first device havinga different direction relative to the first device, determine, based onthe set of beams of the first device, one or more beam switch metricsassociated with a beam switch periodicity for switching a second devicebetween two or more of the set of beams of the first device, andtransmit a report to the first device or a third device that indicatesthe one or more beam switch metrics.

The communications manager 715 may also identify a set of receive beamsassociated with the second device, each of the set of receive beams ofthe second device having a different direction relative to the seconddevice, determine, based on the set of receive beams of the seconddevice, one or more beam switch metrics associated with a beam switchperiodicity for switching the second device between two or more of theset of receive beams, and transmit a report to a first device or a thirddevice that indicates the one or more beam switch metrics. Thecommunications manager 715 may be an example of aspects of thecommunications manager 1010 described herein.

The communications manager 715, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 715, or itssub-components may be executed by a general-purpose processor, a DSP, anapplication-specific integrated circuit (ASIC), a FPGA or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described in the present disclosure.

The communications manager 715, or its sub-components, may be physicallylocated at various positions, including being distributed such thatportions of functions are implemented at different physical locations byone or more physical components. In some examples, the communicationsmanager 715, or its sub-components, may be a separate and distinctcomponent in accordance with various aspects of the present disclosure.In some examples, the communications manager 715, or its sub-components,may be combined with one or more other hardware components, includingbut not limited to an input/output (I/O) component, a transceiver, anetwork server, another computing device, one or more other componentsdescribed in the present disclosure, or a combination thereof inaccordance with various aspects of the present disclosure.

The transmitter 720 may transmit signals generated by other componentsof the device 705. In some examples, the transmitter 720 may becollocated with a receiver 710 in a transceiver module. For example, thetransmitter 720 may be an example of aspects of the transceiver 1020described with reference to FIG. 10. The transmitter 720 may utilize asingle antenna or a set of antennas.

FIG. 8 shows a block diagram 800 of a device 805 that supports beamswitch related information feedback in wireless communications inaccordance with aspects of the present disclosure. The device 805 may bean example of aspects of a device 705, or a UE 115 as described herein.The device 805 may include a receiver 810, a communications manager 815,and a transmitter 835. The device 805 may also include a processor. Eachof these components may be in communication with one another (e.g., viaone or more buses).

The receiver 810 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to beam switchrelated information feedback in wireless communications, etc.).Information may be passed on to other components of the device 805. Thereceiver 810 may be an example of aspects of the transceiver 1020described with reference to FIG. 10. The receiver 810 may utilize asingle antenna or a set of antennas.

The communications manager 815 may be an example of aspects of thecommunications manager 715 as described herein. The communicationsmanager 815 may include a beam identification manager 820, a beam metricmanager 825, and a report manager 830. The communications manager 815may be an example of aspects of the communications manager 1010described herein.

The beam identification manager 820 may identify a set of beamsassociated with a first device, each of the set of beams of the firstdevice having a different direction relative to the first device. Insome cases, the beam identification manager 820 may identify a set ofreceive beams associated with the second device, each of the set ofreceive beams of the second device having a different direction relativeto the second device.

The beam metric manager 825 may determine, based on the set of beams ofthe first device, one or more beam switch metrics associated with a beamswitch periodicity for switching a second device between two or more ofthe set of beams of the first device. In some cases, the beam metricmanager 825 may determine, based on a set of receive beams of the seconddevice, one or more beam switch metrics associated with a beam switchperiodicity for switching the second device between two or more of theset of receive beams.

The report manager 830 may transmit a report to the first device or athird device that indicates the one or more beam switch metrics.

The transmitter 835 may transmit signals generated by other componentsof the device 805. In some examples, the transmitter 835 may becollocated with a receiver 810 in a transceiver module. For example, thetransmitter 835 may be an example of aspects of the transceiver 1020described with reference to FIG. 10. The transmitter 835 may utilize asingle antenna or a set of antennas.

FIG. 9 shows a block diagram 900 of a communications manager 905 thatsupports beam switch related information feedback in wirelesscommunications in accordance with aspects of the present disclosure. Thecommunications manager 905 may be an example of aspects of acommunications manager 715, a communications manager 815, or acommunications manager 1010 described herein. The communications manager905 may include a beam identification manager 910, a beam metric manager915, a report manager 920, a connection establishment manager 925, a SSBbeam trace component 930, and a beam switch periodicity component 935.Each of these modules may communicate, directly or indirectly, with oneanother (e.g., via one or more buses).

The beam identification manager 910 may identify a set of beamsassociated with a first device, each of the set of beams of the firstdevice having a different direction relative to the first device. Insome examples, the beam identification manager 910 may identify a set ofreceive beams associated with the second device, each of the set ofreceive beams of the second device having a different direction relativeto the second device.

In some examples, the beam identification manager 910 may identify a setof cells for which beam switch metrics are measurable. In some examples,the beam identification manager 910 may determine that at least one cellof the set of cells is a mobile cell and that one or more of the set ofcells are stationary cells.

In some examples, the beam identification manager 910 may measure beamswitch metrics of the one or more stationary cells. In some cases, thefirst device and the third device are each base stations, and the seconddevice is a UE. In some cases, the first device and the third device areeach base stations, and the second device is a UE.

The beam metric manager 915 may determine, based on the set of beams ofthe first device, one or more beam switch metrics associated with a beamswitch periodicity for switching a second device between two or more ofthe set of beams of the first device. In some examples, the beam metricmanager 915 may determine, based on a set of receive beams of the seconddevice, one or more beam switch metrics associated with a beam switchperiodicity for switching the second device between two or more of theset of receive beams.

In some examples, the beam metric manager 915 may determine to transmitthe report based on a change in one or more of the beam switch metricsexceeding a threshold value. In some cases, the one or more beam switchmetrics provide information for setting beam management transmissions inaccordance with the beam switch periodicity for switching the seconddevice between the two or more of the set of beams of the first device.

In some cases, beam switch metrics may include one or more of a speed ofthe second device, a Doppler shift of one or more transmission beamsobserved at the second device, a distance between the second device andthe first wireless device 605, a dwelling time that indicates anexpected time duration during which a transmission beam will have morefavorable channel conditions than any other of the set of transmissionbeams of the first device, a dwelling time that indicates an expectedtime duration during which a receive beam of the second device willprovide more favorable receive conditions than any of a set of otherreceive beams of the second device, a time trace of consecutivetransmission beams having a highest quality at the second device for aprior time period, a second device movement profile that includesinformation related to the second device movement speed and direction,spatial location changes, or combinations thereof, a calculated beamswitch periodicity, or any combinations thereof. In some cases, thequality includes one or more of a received signal strength or signal tointerference and noise ratio (SINR).

In some cases, the reported metrics may include an average value of theassociated beam switch metric, a median value of the associated beamswitch metric, a percentile of the associated beam switch metric, amaximum value of the associated beam switch metric during apredetermined time period, a minimum value of the associated beam switchmetric during the predetermined time period, a histogram of observedbeam switch metrics for the predetermined time period, or anycombinations thereof.

The report manager 920 may transmit a report to the first device or athird device that indicates the one or more beam switch metrics. In someexamples, the report manager 920 may receive configuration informationfrom the first device that indicates a periodicity for transmitting thereport. In some examples, the report manager 920 may transmit the reportaccording to the periodicity for transmitting the report. In some cases,the report is transmitted autonomously by the second device. In somecases, the report is transmitted in a MAC-CE. In some cases, the reportfurther includes a cell identification associated with the one or morebeam switch metrics.

The connection establishment manager 925 may receive a controlinformation transmission from the third device that indicates the seconddevice is to transmit the initial access request to the first device,and that indicates one or more SSB transmissions of the first devicethat are to be monitored for reference signal transmissions to determinea preferred transmission beam for subsequent communications with thefirst device.

The SSB beam trace component 930 may identify a first time at which afirst SSB transmission of the first device that has more favorablechannel conditions than one or more other SSB transmissions of the firstdevice. In some examples, the SSB beam trace component 930 may identifya second time at which a second SSB transmission of the first device hasmore favorable channel conditions than the first SSB transmission andone or more other of the SSB transmissions of the first device. In someexamples, the SSB beam trace component 930 may provide at least thefirst time and the second time to the third device in a BST beam switchmetric.

The beam switch periodicity component 935 may determine, based on one ormore of the beam switch metrics, the beam switch periodicity, where thebeam switch periodicity indicates a rate at which transmission beamshaving more favorable transmission beam channel conditions than other ofthe set of transmission beams changes at the second device. In someexamples, the beam switch periodicity component 935 may transmit thedetermined beam switch periodicity to the first device or the seconddevice.

FIG. 10 shows a diagram of a system 1000 including a device 1005 thatsupports beam switch related information feedback in wirelesscommunications in accordance with aspects of the present disclosure. Thedevice 1005 may be an example of or include the components of device705, device 805, or a UE 115 as described herein. The device 1005 mayinclude components for bi-directional voice and data communicationsincluding components for transmitting and receiving communications,including a communications manager 1010, an I/O controller 1015, atransceiver 1020, an antenna 1025, memory 1030, and a processor 1040.These components may be in electronic communication via one or morebuses (e.g., bus 1045).

The communications manager 1010 may identify a set of beams associatedwith a first device, each of the set of beams of the first device havinga different direction relative to the first device, determine, based onthe set of beams of the first device, one or more beam switch metricsassociated with a beam switch periodicity for switching a second devicebetween two or more of the set of beams of the first device, andtransmit a report to the first device or a third device that indicatesthe one or more beam switch metrics.

The communications manager 1010 may also identify a set of receive beamsassociated with the second device, each of the set of receive beams ofthe second device having a different direction relative to the seconddevice, determine, based on the set of receive beams of the seconddevice, one or more beam switch metrics associated with a beam switchperiodicity for switching the second device between two or more of theset of receive beams, and transmit a report to a first device or a thirddevice that indicates the one or more beam switch metrics.

The I/O controller 1015 may manage input and output signals for thedevice 1005. The I/O controller 1015 may also manage peripherals notintegrated into the device 1005. In some cases, the I/O controller 1015may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 1015 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 1015may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 1015may be implemented as part of a processor. In some cases, a user mayinteract with the device 1005 via the I/O controller 1015 or viahardware components controlled by the I/O controller 1015.

The transceiver 1020 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 1020 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1020 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1025.However, in some cases the device may have more than one antenna 1025,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1030 may include RAM and ROM. The memory 1030 may storecomputer-readable, computer-executable code 1035 including instructionsthat, when executed, cause the processor to perform various functionsdescribed herein. In some cases, the memory 1030 may contain, amongother things, a BIOS which may control basic hardware or softwareoperation such as the interaction with peripheral components or devices.

The processor 1040 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1040 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 1040. The processor 1040 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 1030) to cause the device 1005 to perform variousfunctions (e.g., functions or tasks supporting beam switch relatedinformation feedback in wireless communications).

The code 1035 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1035 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1035 may not be directly executable by theprocessor 1040 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 11 shows a block diagram 1100 of a device 1105 that supports beamswitch related information feedback in wireless communications inaccordance with aspects of the present disclosure. The device 1105 maybe an example of aspects of a base station 105 as described herein. Thedevice 1105 may include a receiver 1110, a communications manager 1115,and a transmitter 1120. The device 1105 may also include a processor.Each of these components may be in communication with one another (e.g.,via one or more buses).

The receiver 1110 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to beam switchrelated information feedback in wireless communications, etc.).Information may be passed on to other components of the device 1105. Thereceiver 1110 may be an example of aspects of the transceiver 1420described with reference to FIG. 14. The receiver 1110 may utilize asingle antenna or a set of antennas.

The communications manager 1115 may establish a connection with a seconddevice, receive, from the second device, a report that indicates one ormore beam switch metrics associated with a set of transmission beamsreceived at the second device, determine, based on the report, one ormore beam management parameters for one or more transmissions to thesecond device via one or more of the set of transmission beams, andtransmit the one or more beam management parameters to the seconddevice. The communications manager 1115 may be an example of aspects ofthe communications manager 1410 described herein.

The communications manager 1115, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 1115, or itssub-components may be executed by a general-purpose processor, a DSP, anapplication-specific integrated circuit (ASIC), a FPGA or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described in the present disclosure.

The communications manager 1115, or its sub-components, may bephysically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, thecommunications manager 1115, or its sub-components, may be a separateand distinct component in accordance with various aspects of the presentdisclosure. In some examples, the communications manager 1115, or itssub-components, may be combined with one or more other hardwarecomponents, including but not limited to an input/output (I/O)component, a transceiver, a network server, another computing device,one or more other components described in the present disclosure, or acombination thereof in accordance with various aspects of the presentdisclosure.

The transmitter 1120 may transmit signals generated by other componentsof the device 1105. In some examples, the transmitter 1120 may becollocated with a receiver 1110 in a transceiver module. For example,the transmitter 1120 may be an example of aspects of the transceiver1420 described with reference to FIG. 14. The transmitter 1120 mayutilize a single antenna or a set of antennas.

FIG. 12 shows a block diagram 1200 of a device 1205 that supports beamswitch related information feedback in wireless communications inaccordance with aspects of the present disclosure. The device 1205 maybe an example of aspects of a device 1105, or a base station 105 asdescribed herein. The device 1205 may include a receiver 1210, acommunications manager 1215, and a transmitter 1235. The device 1205 mayalso include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 1210 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to beam switchrelated information feedback in wireless communications, etc.).Information may be passed on to other components of the device 1205. Thereceiver 1210 may be an example of aspects of the transceiver 1420described with reference to FIG. 14. The receiver 1210 may utilize asingle antenna or a set of antennas.

The communications manager 1215 may be an example of aspects of thecommunications manager 1115 as described herein. The communicationsmanager 1215 may include a connection establishment manager 1220, areport manager 1225, and a beam management component 1230. Thecommunications manager 1215 may be an example of aspects of thecommunications manager 1410 described herein.

The connection establishment manager 1220 may establish a connectionwith a second device.

The report manager 1225 may receive, from the second device, a reportthat indicates one or more beam switch metrics associated with a set oftransmission beams received at the second device.

The beam management component 1230 may determine, based on the report,one or more beam management parameters for one or more transmissions tothe second device via one or more of the set of transmission beams andtransmit the one or more beam management parameters to the seconddevice.

The transmitter 1235 may transmit signals generated by other componentsof the device 1205. In some examples, the transmitter 1235 may becollocated with a receiver 1210 in a transceiver module. For example,the transmitter 1235 may be an example of aspects of the transceiver1420 described with reference to FIG. 14. The transmitter 1235 mayutilize a single antenna or a set of antennas.

FIG. 13 shows a block diagram 1300 of a communications manager 1305 thatsupports beam switch related information feedback in wirelesscommunications in accordance with aspects of the present disclosure. Thecommunications manager 1305 may be an example of aspects of acommunications manager 1115, a communications manager 1215, or acommunications manager 1410 described herein. The communications manager1305 may include a connection establishment manager 1310, a reportmanager 1315, a beam management component 1320, a beam switchperiodicity component 1325, a secondary cell manager 1330, a SSB beamtrace component 1335, a beam metric manager 1340, and a configurationmanager 1345. Each of these modules may communicate, directly orindirectly, with one another (e.g., via one or more buses).

The connection establishment manager 1310 may establish a connectionwith a second device.

The report manager 1315 may receive, from the second device, a reportthat indicates one or more beam switch metrics associated with a set oftransmission beams received at the second device. In some examples, thereport manager 1315 may monitor for the report from the second deviceaccording to the periodic transmission schedule. In some cases, thereport is transmitted autonomously by the second device. In some cases,the report is received in a MAC-CE from the second device.

The beam management component 1320 may determine, based on the report,one or more beam management parameters for one or more transmissions tothe second device via one or more of the set of transmission beams. Insome examples, the beam management component 1320 may transmit the oneor more beam management parameters to the second device. In some cases,the first device is a base station, and the second device is a UE. Insome cases, the report further includes a cell identification associatedwith the one or more beam switch metrics.

The beam switch periodicity component 1325 may determine, based on oneor more of the beam switch metrics, a beam switch periodicity of thesecond device that indicates a rate at which transmission beams havingmore favorable transmission beam channel conditions than other of theset of transmission beams changes at the second device, and where theone or more beam management parameters are based on the beam switchperiodicity. In some cases, the one or more beam management parametersinclude a beam switch periodicity for switching the second devicebetween two or more of the set of transmission beams.

The secondary cell manager 1330 may identify, by the first device basedon the one or more beam switch metrics, a first transmission beam of theset of transmission beams for the second device to transmit an initialaccess request to the secondary base station. In some examples, thesecondary cell manager 1330 may provide the secondary base station withthe BST beam switch metric received from the second device. In someexamples, the secondary cell manager 1330 may transmit to the seconddevice, based on the BST beam switch metric, control information for thesecond device monitor one or more SSB transmissions and to transmit theinitial access request.

The SSB beam trace component 1335 may receive a BST from a seconddevice. In some cases, at least a subset of the set of transmissionbeams include a SSB transmission from the secondary base station, andwhere the report includes a BST beam switch metric that indicates two ormore time periods and, for each of the two or more time periods, apreferred SSB of the second device.

In some cases, beam switch metrics may include one or more of a speed ofthe second device, a Doppler shift of one or more transmission beamsobserved at the second device, a distance between the second device andthe first wireless device 605, a dwelling time that indicates anexpected time duration during which a transmission beam will have morefavorable channel conditions than any other of the set of transmissionbeams of the first device, a dwelling time that indicates an expectedtime duration during which a receive beam of the second device willprovide more favorable receive conditions than any of a set of otherreceive beams of the second device, a time trace of consecutivetransmission beams having a highest quality at the second device for aprior time period, a second device movement profile that includesinformation related to the second device movement speed and direction,spatial location changes, or combinations thereof, a calculated beamswitch periodicity, or any combinations thereof. In some cases, thequality includes one or more of a received signal strength or signal tointerference and noise ratio (SINR).

In some cases, the reported metrics may include an average value of theassociated beam switch metric, a median value of the associated beamswitch metric, a percentile of the associated beam switch metric, amaximum value of the associated beam switch metric during apredetermined time period, a minimum value of the associated beam switchmetric during the predetermined time period, a histogram of observedbeam switch metrics for the predetermined time period, or anycombinations thereof.

The configuration manager 1345 may configure the second device totransmit the report based on a change in one or more of the beam switchmetrics exceeding a threshold value. In some examples, the configurationmanager 1345 may configure the second device to transmit the reportaccording to a periodic transmission schedule.

FIG. 14 shows a diagram of a system 1400 including a device 1405 thatsupports beam switch related information feedback in wirelesscommunications in accordance with aspects of the present disclosure. Thedevice 1405 may be an example of or include the components of device1105, device 1205, or a base station 105 as described herein. The device1405 may include components for bi-directional voice and datacommunications including components for transmitting and receivingcommunications, including a communications manager 1410, a networkcommunications manager 1415, a transceiver 1420, an antenna 1425, memory1430, a processor 1440, and an inter-station communications manager1445. These components may be in electronic communication via one ormore buses (e.g., bus 1450).

The communications manager 1410 may establish a connection with a seconddevice, receive, from the second device, a report that indicates one ormore beam switch metrics associated with a set of transmission beamsreceived at the second device, determine, based on the report, one ormore beam management parameters for one or more transmissions to thesecond device via one or more of the set of transmission beams, andtransmit the one or more beam management parameters to the seconddevice.

The network communications manager 1415 may manage communications withthe core network (e.g., via one or more wired backhaul links). Forexample, the network communications manager 1415 may manage the transferof data communications for client devices, such as one or more UEs 115.

The transceiver 1420 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 1420 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1420 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1425.However, in some cases the device may have more than one antenna 1425,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1430 may include RAM, ROM, or a combination thereof. Thememory 1430 may store computer-readable code 1435 including instructionsthat, when executed by a processor (e.g., the processor 1440) cause thedevice to perform various functions described herein. In some cases, thememory 1430 may contain, among other things, a BIOS which may controlbasic hardware or software operation such as the interaction withperipheral components or devices.

The processor 1440 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1440 may be configured to operate a memoryarray using a memory controller. In some cases, a memory controller maybe integrated into processor 1440. The processor 1440 may be configuredto execute computer-readable instructions stored in a memory (e.g., thememory 1430) to cause the device 1405 to perform various functions(e.g., functions or tasks supporting beam switch related informationfeedback in wireless communications).

The inter-station communications manager 1445 may manage communicationswith other base station 105, and may include a controller or schedulerfor controlling communications with UEs 115 in cooperation with otherbase stations 105. For example, the inter-station communications manager1445 may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, the inter-station communications manager1445 may provide an X2 interface within an LTE/LTE-A wirelesscommunication network technology to provide communication between basestations 105.

The code 1435 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1435 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1435 may not be directly executable by theprocessor 1440 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 15 shows a flowchart illustrating a method 1500 that supports beamswitch related information feedback in wireless communications inaccordance with aspects of the present disclosure. The operations ofmethod 1500 may be implemented by a second device (e.g., a UE 115) orits components as described herein. For example, the operations ofmethod 1500 may be performed by a communications manager as describedwith reference to FIGS. 7 through 10. In some examples, a second devicemay execute a set of instructions to control the functional elements ofthe second device to perform the functions described below. Additionallyor alternatively, a second device may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1505, the second device may identify a set of beams associated with afirst device, each of the set of beams of the first device having adifferent direction relative to the first device. The operations of 1505may be performed according to the methods described herein. In someexamples, aspects of the operations of 1505 may be performed by a beamidentification manager as described with reference to FIGS. 7 through10.

At 1510, the second device may determine, based on the set of beams ofthe first device, one or more beam switch metrics associated with a beamswitch periodicity for switching a second device between two or more ofthe set of beams of the first device. The operations of 1510 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1510 may be performed by a beam metricmanager as described with reference to FIGS. 7 through 10.

At 1515, the second device may transmit a report to the first device ora third device that indicates the one or more beam switch metrics. Theoperations of 1515 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1515 may beperformed by a report manager as described with reference to FIGS. 7through 10.

FIG. 16 shows a flowchart illustrating a method 1600 that supports beamswitch related information feedback in wireless communications inaccordance with aspects of the present disclosure. The operations ofmethod 1600 may be implemented by a second device (e.g., a UE 115) orits components as described herein. For example, the operations ofmethod 1600 may be performed by a communications manager as describedwith reference to FIGS. 7 through 10. In some examples, a second devicemay execute a set of instructions to control the functional elements ofthe second device to perform the functions described below. Additionallyor alternatively, a second device may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1605, the second device may identify a set of beams associated with afirst device, each of the set of beams of the first device having adifferent direction relative to the first device. The operations of 1605may be performed according to the methods described herein. In someexamples, aspects of the operations of 1605 may be performed by a beamidentification manager as described with reference to FIGS. 7 through10.

At 1610, the second device may identify a first time at which a firstsynchronization signal block (SSB) transmission of the first device thathas more favorable channel conditions than one or more other SSBtransmissions of the first device. The operations of 1610 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1610 may be performed by a SSB beam tracecomponent as described with reference to FIGS. 7 through 10.

At 1615, the second device may identify a second time at which a secondSSB transmission of the first device has more favorable channelconditions than the first SSB transmission and one or more other of theSSB transmissions of the first device. The operations of 1615 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1615 may be performed by a SSB beam tracecomponent as described with reference to FIGS. 7 through 10.

At 1620, the second device may provide at least the first time and thesecond time to the third device in a best SSB time trace (BST) beamswitch metric. The operations of 1620 may be performed according to themethods described herein. In some examples, aspects of the operations of1620 may be performed by a SSB beam trace component as described withreference to FIGS. 7 through 10.

At 1625, the second device may receive a control informationtransmission from the third device that indicates the second device isto transmit the initial access request to the first device, and thatindicates one or more SSB transmissions of the first device that are tobe monitored for reference signal transmissions to determine a preferredtransmission beam for subsequent communications with the first device.The operations of 1625 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1625may be performed by a connection establishment manager as described withreference to FIGS. 7 through 10.

FIG. 17 shows a flowchart illustrating a method 1700 that supports beamswitch related information feedback in wireless communications inaccordance with aspects of the present disclosure. The operations ofmethod 1700 may be implemented by a second device (e.g. a UE 115) or itscomponents as described herein. For example, the operations of method1700 may be performed by a communications manager as described withreference to FIGS. 7 through 10. In some examples, a second device mayexecute a set of instructions to control the functional elements of thesecond device to perform the functions described below. Additionally oralternatively, a second device may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1705, the second device may identify a set of receive beamsassociated with the second device, each of the set of receive beams ofthe second device having a different direction relative to the seconddevice. The operations of 1705 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1705may be performed by a beam identification manager as described withreference to FIGS. 7 through 10.

At 1710, the second device may determine, based on the set of receivebeams of the second device, one or more beam switch metrics associatedwith a beam switch periodicity for switching the second device betweentwo or more of the set of receive beams. The operations of 1710 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1710 may be performed by a beam metricmanager as described with reference to FIGS. 7 through 10.

At 1715, the second device may transmit a report to a first device or athird device that indicates the one or more beam switch metrics. Theoperations of 1715 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1715 may beperformed by a report manager as described with reference to FIGS. 7through 10.

FIG. 18 shows a flowchart illustrating a method 1800 that supports beamswitch related information feedback in wireless communications inaccordance with aspects of the present disclosure. The operations ofmethod 1800 may be implemented by a first device (e.g. a base station105) or its components as described herein. For example, the operationsof method 1800 may be performed by a communications manager as describedwith reference to FIGS. 11 through 14. In some examples, a first devicemay execute a set of instructions to control the functional elements ofthe first device to perform the functions described below. Additionallyor alternatively, a first device may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1805, the first device may establish a connection with a seconddevice. The operations of 1805 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1805may be performed by a connection establishment manager as described withreference to FIGS. 11 through 14.

At 1810, the first device may receive, from the second device, a reportthat indicates one or more beam switch metrics associated with a set oftransmission beams received at the second device. The operations of 1810may be performed according to the methods described herein. In someexamples, aspects of the operations of 1810 may be performed by a reportmanager as described with reference to FIGS. 11 through 14.

At 1815, the first device may determine, based on the report, one ormore beam management parameters for one or more transmissions to thesecond device via one or more of the set of transmission beams. Theoperations of 1815 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1815 may beperformed by a beam management component as described with reference toFIGS. 11 through 14.

At 1820, the first device may transmit the one or more beam managementparameters to the second device. The operations of 1820 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1820 may be performed by a beam management componentas described with reference to FIGS. 11 through 14.

FIG. 19 shows a flowchart illustrating a method 1900 that supports beamswitch related information feedback in wireless communications inaccordance with aspects of the present disclosure. The operations ofmethod 1900 may be implemented by a second device (e.g. a base station105) or its components as described herein. For example, the operationsof method 1900 may be performed by a communications manager as describedwith reference to FIGS. 11 through 14. In some examples, a first devicemay execute a set of instructions to control the functional elements ofthe first device to perform the functions described below. Additionallyor alternatively, a first device may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1905, the first device may establish a connection with a seconddevice. The operations of 1905 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1905may be performed by a connection establishment manager as described withreference to FIGS. 11 through 14.

At 1910, the first device may receive, from the second device, a reportthat includes a BST beam switch metric that indicates two or more timeperiods and, for each of the two or more time periods, a preferred SSBof a third device that is measured at the second device. The operationsof 1910 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1910 may be performed by areport manager as described with reference to FIGS. 11 through 14.

At 1915, the first device may identify, based on the BST, a firsttransmission beam for the second device to transmit an initial accessrequest to the third device. The operations of 1915 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1915 may be performed by a beam management componentas described with reference to FIGS. 11 through 14.

At 1920, the first device may provide the third device with the BST beamswitch metric received from the second device. The operations of 1920may be performed according to the methods described herein. In someexamples, aspects of the operations of 1920 may be performed by a beammanagement component as described with reference to FIGS. 11 through 14.

At 1925, the first device may transmit to the second device, based onthe BST beam switch metric, control information for the second devicemonitor one or more SSB transmissions and to transmit the initial accessrequest. The operations of 1925 may be performed according to themethods described herein. In some examples, aspects of the operations of1925 may be performed by a secondary cell manager as described withreference to FIGS. 11 through 14.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as code division multiple access (CDMA),time division multiple access (TDMA), frequency division multiple access(FDMA), orthogonal frequency division multiple access (OFDMA), singlecarrier frequency division multiple access (SC-FDMA), and other systems.A CDMA system may implement a radio technology such as CDMA2000,Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000,IS-95, and IS-856 standards. IS-2000 Releases may be commonly referredto as CDMA2000 1X, 1X, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1xEV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical andElectronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications System (UMTS). LTE, LTE-A, and LTE-A Pro are releasesof UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, LTE-A Pro, NR,and GSM are described in documents from the organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned herein as well as other systemsand radio technologies. While aspects of an LTE, LTE-A, LTE-A Pro, or NRsystem may be described for purposes of example, and LTE, LTE-A, LTE-APro, or NR terminology may be used in much of the description, thetechniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro,or NR applications.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell maybe associated with a lower-powered base station, as compared with amacro cell, and a small cell may operate in the same or different (e.g.,licensed, unlicensed, etc.) frequency bands as macro cells. Small cellsmay include pico cells, femto cells, and micro cells according tovarious examples. A pico cell, for example, may cover a small geographicarea and may allow unrestricted access by UEs with service subscriptionswith the network provider. A femto cell may also cover a smallgeographic area (e.g., a home) and may provide restricted access by UEshaving an association with the femto cell (e.g., UEs in a closedsubscriber group (CSG), UEs for users in the home, and the like). An eNBfor a macro cell may be referred to as a macro eNB. An eNB for a smallcell may be referred to as a small cell eNB, a pico eNB, a femto eNB, ora home eNB. An eNB may support one or multiple (e.g., two, three, four,and the like) cells, and may also support communications using one ormultiple component carriers.

The wireless communications systems described herein may supportsynchronous or asynchronous operation. For synchronous operation, thebase stations may have similar frame timing, and transmissions fromdifferent base stations may be approximately aligned in time. Forasynchronous operation, the base stations may have different frametiming, and transmissions from different base stations may not bealigned in time. The techniques described herein may be used for eithersynchronous or asynchronous operations.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA, or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices(e.g., a combination of a DSP and a microprocessor, multiplemicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude random-access memory (RAM), read-only memory (ROM), electricallyerasable programmable ROM (EEPROM), flash memory, compact disk (CD) ROMor other optical disk storage, magnetic disk storage or other magneticstorage devices, or any other non-transitory medium that can be used tocarry or store desired program code means in the form of instructions ordata structures and that can be accessed by a general-purpose orspecial-purpose computer, or a general-purpose or special-purposeprocessor. Also, any connection is properly termed a computer-readablemedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition of medium.Disk and disc, as used herein, include CD, laser disc, optical disc,digital versatile disc (DVD), floppy disk and Blu-ray disc where disksusually reproduce data magnetically, while discs reproduce dataoptically with lasers. Combinations of the above are also includedwithin the scope of computer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an exemplary step that is described as “based on conditionA” may be based on both a condition A and a condition B withoutdeparting from the scope of the present disclosure. In other words, asused herein, the phrase “based on” shall be construed in the same manneras the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method for wireless communication at a seconddevice comprising: identifying a plurality of beams associated with afirst device, each of the plurality of beams of the first device havinga different transmission configuration indicator state and a differentdirection relative to the first device; determining, based at least inpart on the plurality of beams of the first device, one or more beamswitch metrics associated with a beam switch periodicity for switchingthe second device between two or more of the plurality of beams of thefirst device; and transmitting a report to the first device or a thirddevice that indicates the one or more beam switch metrics.
 2. The methodof claim 1, wherein the first device and the third device are each basestations, and the second device is a user equipment (UE).
 3. The methodof claim 1, wherein the one or more beam switch metrics provideinformation for setting beam management transmissions in accordance withthe beam switch periodicity for switching the second device between thetwo or more of the plurality of beams of the first device.
 4. The methodof claim 1, wherein the report is transmitted to the third device, andthe one or more beam switch metrics provide information for selecting afirst transmission beam for transmitting an initial access request tothe first device.
 5. The method of claim 4, further comprising:identifying a first time at which a first synchronization signal block(SSB) transmission of the first device that has more favorable channelconditions than one or more other SSB transmissions of the first device;identifying a second time at which a second SSB transmission of thefirst device has more favorable channel conditions than the first SSBtransmission and one or more other of the SSB transmissions of the firstdevice; and providing at least the first time and the second time to thethird device in a best SSB time trace (BST) beam switch metric.
 6. Themethod of claim 5, further comprising: receiving a control informationtransmission from the third device that indicates the second device isto transmit the initial access request to the first device, and thatindicates one or more SSB transmissions of the first device that are tobe monitored for reference signal transmissions to determine a preferredtransmission beam for subsequent communications with the first device.7. The method of claim 1, further comprising: determining, based atleast in part on one or more of the beam switch metrics, the beam switchperiodicity, wherein the beam switch periodicity indicates a rate atwhich transmission beams having more favorable transmission beam channelconditions than other of the plurality of transmission beams changes atthe second device; and transmitting the determined beam switchperiodicity to the first device or the third device.
 8. The method ofclaim 1, wherein the one or more beam switch metrics comprise one ormore of: a speed of the second device; a Doppler shift of one or moretransmission beams observed at the second device; a distance between thesecond device and the first device; a dwelling time that indicates anexpected time duration during which a transmission beam will have morefavorable channel conditions than any other of the plurality oftransmission beams of the first device; a dwelling time that indicatesan expected time duration during which a receive beam of the seconddevice will provide more favorable receive conditions than any of aplurality of other receive beams of the second device; a time trace ofconsecutive transmission beams having a highest quality at the seconddevice for a prior time period, wherein the quality includes one or moreof a received signal strength or signal to interference and noise ratio(SINK); a second device movement profile that comprises informationrelated to the second device movement speed and direction, spatiallocation changes, or combinations thereof; a calculated beam switchperiodicity; or any combinations thereof.
 9. The method of claim 8,wherein the beam switch metrics comprise statistics that indicate one ormore of: an average value of the associated beam switch metric; a medianvalue of the associated beam switch metric; a percentile of theassociated beam switch metric; a maximum value of the associated beamswitch metric during a predetermined time period; a minimum value of theassociated beam switch metric during the predetermined time period; ahistogram of observed beam switch metrics for the predetermined timeperiod; or any combinations thereof.
 10. The method of claim 1, furthercomprising: determining to transmit the report based at least in part ona change in one or more of the beam switch metrics exceeding a thresholdvalue, and wherein the report is transmitted autonomously by the seconddevice.
 11. The method of claim 1, further comprising: receivingconfiguration information from the first device that indicates aperiodicity for transmitting the report; and transmitting the reportaccording to the periodicity for transmitting the report.
 12. The methodof claim 1, wherein the report further comprises a cell identificationassociated with the one or more beam switch metrics, and wherein themethod further comprises: identifying a plurality of cells for whichbeam switch metrics are measurable; determining that at least one cellof the plurality of cells is a mobile cell and that one or more of theplurality of cells are stationary cells; and measuring the beam switchmetrics of the one or more stationary cells.
 13. A method for wirelesscommunication at a second device comprising: identifying a plurality ofreceive beams associated with the second device, each of the pluralityof receive beams of the second device having a different transmissionconfiguration indicator state and a different direction relative to thesecond device; determining, based at least in part on the plurality ofreceive beams of the second device, one or more beam switch metricsassociated with a beam switch periodicity for switching the seconddevice between two or more of the plurality of receive beams; andtransmitting a report to a first device or a third device that indicatesthe one or more beam switch metrics.
 14. The method of claim 13, whereinthe first device and the third device are each base stations, and thesecond device is a user equipment (UE).
 15. The method of claim 13,wherein the one or more beam switch metrics provide information forsetting beam management transmissions in accordance with the beam switchperiodicity for switching the second device between the two or more ofthe plurality of receive beams of the second device.
 16. The method ofclaim 13, wherein the one or more beam switch metrics comprise one ormore of: a speed of the second device; a Doppler shift of one or moretransmission beams observed at the second device; a distance between thesecond device and the first device; a dwelling time that indicates anexpected time duration during which a transmission beam of the firstdevice will have more favorable channel conditions than any other of aplurality of transmission beams of the first device; a dwelling timethat indicates an expected time duration during which a receive beam ofthe second device will provide more favorable receive conditions thanany other of the plurality of receive beams of the second device; asecond device movement profile that comprises information related to thesecond device movement speed and direction, spatial location changes, orcombinations thereof; a calculated beam switch periodicity; or anycombinations thereof.
 17. The method of claim 16, wherein the beamswitch metrics comprise statistics that indicate one or more of: anaverage value of the associated beam switch metric; a median value ofthe associated beam switch metric; a percentile of the associated beamswitch metric; a maximum value of the associated beam switch metricduring a predetermined time period; a minimum value of the associatedbeam switch metric during the predetermined time period; a histogram ofobserved beam switch metrics for the predetermined time period; or anycombinations thereof.
 18. A method for wireless communication at a firstdevice, comprising: establishing a connection with a second device;receiving, from the second device, a report that indicates one or morebeam switch metrics associated with a plurality of transmission beamsreceived at the second device, wherein each of the plurality oftransmission beams has a different transmission configuration indicatorstate; determining, based at least in part on the report, one or morebeam management parameters for one or more transmissions to the seconddevice via one or more of the plurality of transmission beams; andtransmitting the one or more beam management parameters to the seconddevice.
 19. The method of claim 18, wherein the first device is a basestation, and the second device is a user equipment (UE).
 20. The methodof claim 18, wherein the one or more beam management parameters comprisea beam switch periodicity for switching the second device between two ormore of the plurality of transmission beams.
 21. The method of claim 18,wherein the first device is a primary base station in a non-stand-alone(NSA) deployment, and the plurality of transmission beams aretransmitted by a secondary base station in the NSA deployment, andwherein the method further comprises: identifying, by the first devicebased at least in part on the one or more beam switch metrics, a firsttransmission beam of the plurality of transmission beams for the seconddevice to transmit an initial access request to the secondary basestation.
 22. The method of claim 21, wherein at least a subset of theplurality of transmission beams include a synchronization signal block(SSB) transmission from the secondary base station, and wherein thereport includes a best SSB time trace (BST) beam switch metric thatindicates two or more time periods and, for each of the two or more timeperiods, a preferred SSB of the second device.
 23. The method of claim22, further comprising: providing the secondary base station with theBST beam switch metric received from the second device; and transmittingto the second device, based at least in part on the BST beam switchmetric, control information for the second device monitor one or moreSSB transmissions and to transmit the initial access request.
 24. Themethod of claim 18, further comprising: determining, based at least inpart on one or more of the beam switch metrics, a beam switchperiodicity of the second device that indicates a rate at whichtransmission beams having more favorable transmission beam channelconditions than other of the plurality of transmission beams changes atthe second device, and wherein the one or more beam managementparameters are based at least in part on the beam switch periodicity.25. An apparatus for wireless communication at a second devicecomprising, comprising: a processor, memory in electronic communicationwith the processor; and instructions stored in the memory and executableby the processor to cause the apparatus to: identify a plurality ofbeams associated with a first device, each of the plurality of beams ofthe first device having a different transmission configuration indicatorstate and a different direction relative to the first device; determine,based at least in part on the plurality of beams of the first device,one or more beam switch metrics associated with a beam switchperiodicity for switching a second device between two or more of theplurality of beams of the first device; and transmit a report to thefirst device or a third device that indicates the one or more beamswitch metrics.
 26. The apparatus of claim 25, wherein the one or morebeam switch metrics provide information for setting beam managementtransmissions in accordance with the beam switch periodicity forswitching the second device between the two or more of the plurality ofbeams of the first device.
 27. The apparatus of claim 25, wherein thereport is transmitted to the third device, and the one or more beamswitch metrics provide information for selecting a first transmissionbeam for transmitting an initial access request to the first device. 28.The apparatus of claim 27, wherein the instructions are furtherexecutable by the processor to cause the apparatus to: identify a firsttime at which a first synchronization signal block (SSB) transmission ofthe first device that has more favorable channel conditions than one ormore other SSB transmissions of the first device; identify a second timeat which a second SSB transmission of the first device has morefavorable channel conditions than the first SSB transmission and one ormore other of the SSB transmissions of the first device; and provide atleast the first time and the second time to the third device in a bestSSB time trace (BST) beam switch metric.
 29. The apparatus of claim 28,wherein the instructions are further executable by the processor tocause the apparatus to: receive a control information transmission fromthe third device that indicates the second device is to transmit theinitial access request to the first device, and that indicates one ormore SSB transmissions of the first device that are to be monitored forreference signal transmissions to determine a preferred transmissionbeam for subsequent communications with the first device.
 30. Theapparatus of claim 25, wherein the instructions are further executableby the processor to cause the apparatus to: determine, based at least inpart on one or more of the beam switch metrics, the beam switchperiodicity, wherein the beam switch periodicity indicates a rate atwhich transmission beams having more favorable transmission beam channelconditions than other of the plurality of transmission beams changes atthe second device; and transmit the determined beam switch periodicityto the first device or the second device.